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Article History

Received: 31 May 2025

Accepted: 28 October 2025

First Online: 27 November 2025

Declarations

:

: The authors declare no competing interests.

: The data utilized in this study is derived from the “China Longitudinal Ageing Social Survey” (CLASS), conducted by Renmin University of China. The CLASS survey is a sociological research project and does not fall within the realm of medical research. It adheres to the ethical standards outlined in the Declaration of Helsinki and does not involve human experimentation as defined by that Declaration. Furthermore, the questionnaire is specifically designed to avoid any adverse effects on the health of the respondents. Consequently, the CLASS survey does not require additional ethical approval. All participants provided written informed consent, and the information collected is intended exclusively for sociological research purposes, with strict measures in place to ensure confidentiality and anonymity.

: The interviewer recorded more detailed information regarding the informed consent process, including whether participants agreed to take part in the study and the timing of their consent. The details of the informed consent process are maintained by the Institute of Gerontology at Renmin University of China and the National Survey Research Center.